¿How to know my tonalamatl with the mexican calendar?

There are four year-signs within the Mexican calendar: Calli(House), Tochtli(Rabbit), Acatl(Reed), and Tecpatl(Flint). Each sign has its days commencing at the same hour; once four years have passed, an entire day is recovered. These years occur in a cyclical fashion, numbered from ce (one) to matlactli ihuan yei (thirteen), formulating a unique count which generates even greater time cycles. A "century" within our calendarical system begins at Ce-Tochtli(One-Rabbit); the first thirteen years make uo one tlalpilli, of which they are presided over by Ce-Tochtli, or a tlalpilli tochtli.

There exist two calendars within the Mexican calendarical system, that rotate in a parallel, cyclical fashion, such as in the gears of a wheel, and allow a coexisting relationship over an enormous period of time. One of such components is the xiuhmolpilli, or the solar calendar, whose lenght is 365 days and a quarter, divided into eighteen, twenty-day "months" an additional five-day nemontemi period, or "days that which end a year" and as previously mentioned, the final quarter of the day that ultimately concludes the year. Each month begins with the day-sign cipactli, or crocodile, and ends with xochitl, flower.

The other component is a ritual count of 260 days, known as the tonalpohualli, comprised of twenty, thirteen-day periods, which are numbered from ce (one) to matlactli ihuan yei (thirteen). For every first day of each period, which can be found inscribed in the tonalamatl codices, also referred to as the books of destinies.

Tonalpohualli: The calendarical system to know your birthday "tonalamatl"

The twenty thirteen-day periods of the ritual calendar

Years of tlalpilli

The first step to know your tonalamatl is getting the year of your birthday.

The Signs of the Day

After the location of your year of birth, you need to know your sign of the day. For example, if you born in a cipactli day (crocodile day) it means origin and age; commencement and evolution. refers to the prehistoric past among the lagoons, riverbanks, marshes and swamps. Conceptually, its representation encompasses the beginning and evolution of all beings.

Numbers

As a numeral base, the number thirteen is often related to wisdom; given it is the starting point of becoming acquainted with many cosmic cycles, as well as gestational cycles of all beings, including the woman.

You also got a number from your tonalpohualli

The twenty, thirteen-day periods

The thirteen-day periods is also fundamental to get a full tonalamatl review of one person.